"use client";

import { useMemo, useState, type KeyboardEvent } from "react";
import { LoaderCircle, MapPin, Search, X } from "lucide-react";
import { CurrentLocationControl } from "@/components/weather/current-location-control";
import { useLocationSearch } from "@/hooks/use-location-search";
import { useI18n } from "@/lib/i18n";
import { createSelectedLocation, locateSynopStations } from "@/lib/location-utils";
import { useWeatherStore } from "@/lib/store";
import { formatDistance } from "@/lib/weather-utils";
import type { MeteoStationPosition, SynopStation } from "@/types/imgw";
import type { SelectedLocation } from "@/types/location";

export function LocationSearch({
  stations,
  positions,
}: {
  stations: SynopStation[];
  positions: MeteoStationPosition[];
}) {
  const { language, t } = useI18n();
  const [query, setQuery] = useState("");
  const [isFocused, setIsFocused] = useState(false);
  const selectedLocation = useWeatherStore((state) => state.selectedLocation);
  const distanceUnit = useWeatherStore((state) => state.distanceUnit);
  const selectLocation = useWeatherStore((state) => state.selectLocation);
  const { data: locations, isFetching, isError } = useLocationSearch(query, language);
  const locatedStations = useMemo(() => locateSynopStations(stations, positions), [positions, stations]);
  const suggestions = useMemo(
    () =>
      (locations ?? []).map((location) => ({
        location,
        selected: createSelectedLocation(location, locatedStations),
      })),
    [locatedStations, locations],
  );
  const showSuggestions = isFocused && query.trim().length >= 2;
  const isPreparingStations =
    positions.length === 0 && suggestions.some(({ selected }) => selected.region === "PL" && !selected.stationName);

  function chooseLocation(location: SelectedLocation) {
    selectLocation(location);
    setQuery("");
    setIsFocused(false);
  }

  function handleSearchKeyDown(event: KeyboardEvent<HTMLInputElement>) {
    const firstSuggestion = suggestions[0]?.selected;
    if (event.key !== "Enter" || !showSuggestions || !firstSuggestion) return;
    event.preventDefault();
    chooseLocation(firstSuggestion);
  }

  return (
    <section className="relative z-30">
      <div className="glass rounded-panel p-3 sm:p-4">
        <div className="flex items-center gap-2 px-1 pb-3">
          <MapPin className="size-4 text-accent" />
          <p className="section-kicker">{t("location.label")}</p>
        </div>
        <div className="relative z-20">
          <label className="relative block">
            <span className="sr-only">{t("location.searchLabel")}</span>
            {isFetching || isPreparingStations ? (
              <LoaderCircle className="pointer-events-none absolute left-3.5 top-1/2 size-4 -translate-y-1/2 animate-spin text-accent" />
            ) : (
              <Search className="pointer-events-none absolute left-3.5 top-1/2 size-4 -translate-y-1/2 text-muted" />
            )}
            <input
              value={query}
              onChange={(event) => setQuery(event.target.value)}
              onKeyDown={handleSearchKeyDown}
              onFocus={() => setIsFocused(true)}
              onBlur={() => window.setTimeout(() => setIsFocused(false), 150)}
              placeholder={t("location.placeholder")}
              autoComplete="off"
              className="w-full rounded-card border border-border/70 bg-surface-raised/80 py-3.5 pl-10 pr-10 text-base placeholder:text-muted focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent sm:text-sm"
            />
            {query && (
              <button
                type="button"
                aria-label={t("location.clear")}
                onClick={() => setQuery("")}
                className="absolute right-3 top-1/2 -translate-y-1/2 rounded-control p-1 text-muted transition hover:bg-surface-muted/70 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent"
              >
                <X className="size-4" />
              </button>
            )}
          </label>
          {showSuggestions && (
            <div className="glass absolute inset-x-0 top-[calc(100%+0.5rem)] overflow-hidden rounded-panel p-2 shadow-card">
              {isPreparingStations ? (
                <p className="px-3 py-4 text-sm text-muted">{t("location.preparing")}</p>
              ) : isError ? (
                <p className="px-3 py-4 text-sm text-muted">{t("location.error")}</p>
              ) : !isFetching && !suggestions.length ? (
                <p className="px-3 py-4 text-sm text-muted">{t("location.empty")}</p>
              ) : (
                suggestions.map(({ location, selected }) => (
                  <button
                    type="button"
                    key={location.id}
                    onClick={() => chooseLocation(selected)}
                    className="flex w-full items-start justify-between gap-3 rounded-card px-3 py-3 text-left transition hover:bg-surface-muted/70 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent"
                  >
                    <span>
                      <span className="block text-sm font-semibold">{location.name}</span>
                      <span className="mt-0.5 block text-xs text-muted">
                        {[location.admin2, location.admin1, location.country].filter(Boolean).join(" · ")}
                      </span>
                    </span>
                    {selected.stationName && selected.distanceKm !== null ? (
                      <span className="shrink-0 text-right text-[0.68rem] leading-5 text-muted">
                        {t("location.nearest")}
                        <br />
                        <strong className="font-semibold text-foreground">
                          {selected.stationName} · {formatDistance(selected.distanceKm, language, distanceUnit)}
                        </strong>
                      </span>
                    ) : (
                      <span className="shrink-0 text-right text-[0.68rem] leading-5 text-muted">
                        {t("location.modelSource")}
                        <br />
                        <strong className="font-semibold text-foreground">Open-Meteo</strong>
                      </span>
                    )}
                  </button>
                ))
              )}
            </div>
          )}
        </div>
        <CurrentLocationControl stations={locatedStations} />
        {selectedLocation && (
          <p className="mt-3 px-1 text-xs text-muted">
            {selectedLocation.stationName && selectedLocation.distanceKm !== null
              ? t("location.currentSource", {
                  location: selectedLocation.name,
                  station: selectedLocation.stationName,
                  distance: formatDistance(selectedLocation.distanceKm, language, distanceUnit),
                })
              : t("location.currentSourceGlobal", { location: selectedLocation.name })}
          </p>
        )}
        <p className="mt-3 px-1 text-[0.68rem] text-muted">
          {t("location.attribution")}{" "}
          <a
            href="https://open-meteo.com/en/docs/geocoding-api"
            target="_blank"
            rel="noreferrer"
            className="underline decoration-muted/60 underline-offset-2 transition hover:text-accent"
          >
            Open-Meteo / GeoNames
          </a>
        </p>
      </div>
    </section>
  );
}